1. Technical Field
The present invention relates to a laser light source, a laser light source unit, an illumination device, a monitor apparatus, and an image display apparatus.
2. Related Art
A semiconductor laser element generates heat at the time of light irradiation, and thus, in the related art, a scheme that a semiconductor laser device is formed by fixing a semiconductor laser element on a submount formed of a material good in thermal conductivity for easily releasing heat to the outside has been proposed (e.g., see JP-A-2005-347590).
However, a semiconductor laser array is easy to release heat at both ends closer to the outer circumference and hard to release heat at the center, and thus, the temperature is higher at the center than at the both ends. Thereby, there are temperature differences among the respective light exiting regions (emitters) of the semiconductor laser array. Sometimes the semiconductor laser elements are arrayed for increasing output at a specific oscillation wavelength, however, there is a problem that the laser output decreases at the specific wavelength because the oscillation wavelengths differ from one light exiting region to another when there are temperature differences among the respective light exiting regions.
Especially, when the array is used in combination with a wavelength conversion element, since the wavelength conversion element performs efficient conversion at a wavelength, there is a problem that the laser output from the light exiting region that oscillates at another wavelength decreases.
Further, in the case of using an external resonant mirror, since the wavelength at which laser oscillation is the most efficient differs from one light exiting region to another, there is a problem that the light exiting region that provides low laser output is emerged and the total output decreases because the match is impossible between the oscillation wavelengths in all light exiting regions and the laser wavelength of the resonance by the external resonant mirror.